This invention relates to a buckling device for connecting vehicle occupant restraint belts.
In the prior art, a buckling device of related type comprises a locking means disposed in a frame so as to be always spring urged in the direction of a tongue plate having an aperture is to be locked. The prior art construction is such that when the tongue plate is inserted into the frame, the tongue plate brings the peripheral end of said aperture into engagement with said locking means to lock the tongue plate. With the inserting of the tongue plate into the frame, however, the tongue plate is exposed to a clamping-like force between the frame and the locking means so that the locking means is likely held in the clamped condition even though the inserting operation is suspended on its way. Hence, the locking means tightly contacts with the surface of the tongue plate even before the tongue plate is locked. Because of, as it were, the spuriously locked condition, it should be apparent that an occupant can mistakenly finish the locking operation with the tongue plate incompletely locked.
In consequence, there is the possible hazard that occupant restraint belts can be easily disconnected so that the vehicle occupant would get seriously injured at the time of collision or the like.
On the other hand, when the buckle means is wholly subjected to a strong impact for some unknown cause, there is also the of danger that the locking means can accidentally get out from the aperture of the tongue plate to dislodge the locked tongue plate.